In an input-output device having a logical operation function for setting a signal, two states of ON and OFF of which are defined by voltage values, as an input signal and controlling an ON state and an OFF state of a plurality of outputs when the input signal is in the ON state, even if ON conditions of the input signal are defined by a plurality of voltage values, there is only one kind of a voltage condition defined on an input port side. Therefore, an output signal cannot be selected according to a difference in a voltage value of the input signal.
When the ON state and the OFF state of the output signal is selected according to the difference in the voltage value of the input signal, it is necessary to connect the input signal to a plurality of input ports having ON conditions under which the output signal can be recognized as ON at all of a plurality of voltage values of the input signal.
In an input-output device in which the input signal is connected to the plurality of input ports having the ON conditions under which the output signal can be recognized as ON at all of the plurality of voltage values of the input signal, when ON is detected in any one of the input ports divided from the input signal and connected, by controlling the ON state and the OFF state of the output signal from an output port set in advance, it is possible to select the output signal according to a difference in a voltage value of the input signal.
When the ON state and the OFF state of the output signal are selected according to a difference in a current value of the input signal, it is necessary to connect the input signal to a plurality of input ports having ON conditions under which the output signal can be recognized as ON at all of a plurality of current values of the input signal.
In an input-output device in which the input signal is connected to the plurality of input ports having the ON conditions under which the output signal can be recognized as ON at all of the plurality of voltage values of the input signal, when ON is detected in any one of the input ports divided from the input signal and connected, by controlling the ON state and the OFF state of the output signal from an output port set in advance, it is possible to select the output signal according to a difference in a current value of the input signal.
When the ON state and the OFF state of the output signal are selected according to a difference in an ON time of the input signal, in the same manner as when the ON state and the OFF state of the output signal are selected according to the difference in the voltage value or the current value, it is necessary to connect the input signal to a plurality of input ports having ON conditions under which the output signal can be recognized as ON at all of a plurality of ON times of the input signal.
Further, when the ON conditions of the input signal are defined by combinations of the voltage value, the current value, and the ON time, input ports as many as the number of combinations are necessary. It is necessary to connect the input signal to the input ports.
A technology for determining in which state an input signal having a plurality of states is in is disclosed in Patent Literature 1.